Fencing & Boundaries Calculators

Fencing is one of the most common home improvement projects in the UK, with millions of fence panels sold every year. Whether you are replacing storm-damaged panels, installing a new garden boundary, or upgrading to a more attractive style, calculating the correct number of panels, posts, and fixings is the first step to a successful project.

Standard UK fence panels are 1.83m (6 feet) wide, available in heights of 0.9m (3 feet), 1.2m (4 feet), 1.5m (5 feet), and 1.83m (6 feet). The most common panel types are closeboard (featheredge), lap panels, and hit-and-miss panels. Closeboard fencing is the most durable and is constructed from individual featheredge boards nailed to arris rails, while lap and hit-and-miss panels are pre-made. Our fence panel calculator works out how many panels and posts you need for any boundary length, accounting for end posts and corner posts.

Fence posts in the UK are typically 75mm × 75mm or 100mm × 100mm pressure-treated softwood, with lengths of 2.4m for 1.83m high fencing (allowing 600mm to be set into the ground). Posts are either concreted in (using Postcrete quick-set post mix or a standard concrete mix) or set using bolt-down post supports for hard surfaces. Our concrete for fence posts calculator estimates exactly how many bags of Postcrete or how much concrete you need for your fence run.

Gravel boards sit at the bottom of the fence, between the posts and the ground, to protect the fence panels from moisture and soil contact. They are available in concrete (150mm × 1830mm, the most durable option) or timber (typically 150mm × 1.83m treated softwood). Our gravel board calculator estimates the number of gravel boards and fixing clips needed for your fence.

UK law regarding garden fences is often misunderstood. Under Permitted Development rights, a fence in a rear garden can be up to 2 metres high without planning permission, while a fence adjacent to a highway must not exceed 1 metre. There is no legal obligation to erect or maintain a boundary fence unless a covenant exists in the property deeds. The “left-hand rule” for fence ownership is a common myth — ownership is determined by the title deeds, not by which side the posts are on. If you are replacing an existing fence, check your deeds or the Land Registry title plan to confirm ownership before proceeding.